The dangers of free flight of a ski, which can carom downhill out of the control of the skier upon inadvertent release of the ski from the ski boot or binding has long concerned the art. It has been proposed to avoid such free flight by attaching a safety strap between the leg of the skier and the ski. Devices of this type are restrictive and frequently are not sufficiently reliable to completely solve the problem. Furthermore, a tether of this type requires additional manipulation in mounting the ski on the ski boot and may be avoided by the skier.
To overcome these problems and prevent injury to those persons on the slope, it has been proposed to provide the ski with a so-called ski brake designed to present a brake element or member to the snow and thereby restrict free flight of the ski, the brake element being placed in its operative position automatically upon release of the ski boot or binding from the upper surface of the ski.
For example, one such ski brake has a shank rotatable about an axis perpendicular to the longitudinal axis of the ski by a spring force, thereby rotating the brake element into its operative position upon opening or release of the ski binding. The brake element or spike thereupon swings into a position in which it projects beyond the running surface of the ski. While this system has been found to be effective, especially when the shank extends across the ski and is provided with such spikes along either longitudinal edge to increase the effectiveness of braking, it has been found that the device tends to ice up and jam so that it is of dubious reliability.
In general, when the brake device has been provided with rotating axles, helical or spiral springs, bearings to effect rotation and like elements, blocking or jamming of the device with snow or ice has been a problem. The problem has been found to remain even when the spring assembly and bearings are received in a housing structure.
Another disadvantage of conventional structures is the height or thickness of the housing assembly when numerous parts are provided to generate the spring action and the rotation. Since the ski brake actuator should preferably be provided between the ski boot or binding mounting plate and the upper surface of the ski, any excessive height of such housings and mechanisms, any unduly large spring arrangement or bearing mechanism interferes with satisfactory positioning of the device.
It has been proposed to provide a relatively flat mounting for a ski brake in which, for example, a spring wire loop has a pair of legs received in a mounting plate and carries a spike or brake element which lies along one side of the ski. This system, while free from some of the disadvantages enumerated above acts asymmetrically and hence unreliably. The assembly is also difficult and expensive to construct and cannot always be actuated or inactivated effectively.